A sample injector and control for precise quantitative measurement of environmental gases

Abstract

The present invention discloses an injector and control for precise quantification of environmental gases, and relates to the technical field of analytical instruments. It comprises a filter, a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, a passivation gas path block, a quantitative ring, and an air pump connected in a pipeline manner and a control circuit. The use and operation of the injector of the present invention also includes six control processes, namely, a sampling stage, an injection stage, a cavity pressurization stage during the pipeline cleaning process, a filter backwashing stage during the pipeline cleaning process, a cavity re-pressurization stage during the pipeline cleaning process, and a quantitative ring flushing stage during the pipeline cleaning process. The present invention proposes a miniaturized, modular, low-power, and low-cost injection device to ensure accurate quantification, stability, and repeatability of sample collection, and provides a solid technical and material foundation for future analytical instruments, especially pre-treatment systems of online and portable analytical instruments, and has a profound reference significance.

Description

Technical Field

[0001] The invention relates to the technical field of analytical instruments, and in particular to a sample injector and control device for precise quantitative analysis of environmental gases. Background Art

[0002] The sample injector is the pre-treatment system of the analytical instrument. Its main function is to complete the collection of samples to be analyzed, and accurate quantification and injection during the sample collection process are crucial to the stability and repeatability of the analytical instrument. At present, in the process of sample collection, for field environmental detection instruments, especially portable analytical instruments, most of them use six-way valves or ten-way valves, plus switch solenoid valves, etc. to realize sample collection and injection. This method is not only costly, but also easy to cause the six-way valve or ten-way valve to be contaminated or even blocked in harsh environments. This not only increases the maintenance cost of the instrument, but also is very unfavorable to the stability and repeatability of the analytical instrument. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies and shortcomings of the prior art and to provide an accurate quantitative sampling and injector for field environmental testing instruments.

[0004] The invention discloses an injector for precise quantitative measurement of environmental gas, comprising a filter, a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, a passivation gas path block, a quantitative ring, an air pump connected in a pipeline manner and a control circuit board.

[0005] Wherein, one end of the first solenoid valve is connected to the filter, and the other end is connected to the injector inlet of the passivation gas block;

[0006] One end of the second solenoid valve is connected to the vacuum pump, and the other end is connected to the vent of the passivation gas path block;

[0007] One end of the third solenoid valve is connected to the vent port of the passivation gas circuit block, and the other end is connected to the analytical instrument inlet of the passivation gas circuit block;

[0008] One end of the fourth solenoid valve is connected to the carrier gas inlet of the passivation gas path block, and the other end is connected to the analytical instrument inlet of the passivation gas path block;

[0009] One end of the fifth solenoid valve is connected to the carrier gas inlet of the passivation gas path block, and the other end is connected to the injector inlet of the passivation gas path block;

[0010] One end of the quantitative loop is connected to the injector inlet of the passivation gas path block, and the other end is connected to the vent of the passivation gas path block;

[0011] The passivation gas block is made of aluminum alloy or stainless steel and has been passivated. The quantitative ring is made of stainless steel and has been passivated.

[0012] The present invention provides a control of a sampler for precise quantitative measurement of environmental gases, and also includes six control processes, namely, a sampling stage, a sample injection stage, a cavity pressurizing stage during pipeline cleaning, a filter backwashing stage during pipeline cleaning, a cavity re-pressurizing stage during pipeline cleaning, and a quantitative loop flushing stage during pipeline cleaning.

[0013] During the sampling stage, the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are opened, the third solenoid valve and the fifth solenoid valve are closed, and the vacuum pump is turned on. The ambient gas is discharged from the sampler inlet through the filter, the quantitative ring, and the vacuum pump, and the carrier gas enters the analyzer inlet from the carrier gas inlet.

[0014] In the injection stage, the first solenoid valve, the second solenoid valve, and the fourth solenoid valve are closed, the third solenoid valve and the fifth solenoid valve are opened, the vacuum pump is closed, and the carrier gas enters from the carrier gas inlet to bring the gas to be tested in the quantitative loop into the analytical instrument for detection.

[0015] During the cavity pressurization stage in the pipeline cleaning process, the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are closed, the fifth solenoid valve is opened, the vacuum pump is in a closed state, the carrier gas enters the quantitative ring from the carrier gas inlet, and the cavity is pressurized.

[0016] During the filter backflushing stage in the pipeline cleaning process, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are closed, the first solenoid valve and the fifth solenoid valve are opened, and the pressurized carrier gas is discharged through the injector inlet, thereby backflushing the filter.

[0017] During the cavity re-pressurization stage in the pipeline cleaning process, the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve are closed, the fifth solenoid valve is opened, the vacuum pump is in a closed state, the carrier gas enters the quantitative ring from the carrier gas inlet, and the cavity is pressurized again.

[0018] During the quantitative loop flushing stage of the pipeline cleaning process, the first solenoid valve and the third solenoid valve are closed, the fourth solenoid valve is closed, the second solenoid valve and the fifth solenoid valve are opened, and the pressurized carrier gas is discharged through the vent to flush the quantitative loop.

[0019] The beneficial effect of the present invention is that it breaks the defects of the existing sampling technology and provides a miniaturized, modular, low-power, low-cost sampling device, which ensures the accurate quantification of sample collection and has far-reaching reference significance for future analytical instruments, especially the pre-treatment systems of online and portable analytical instruments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of a precise quantitative sample injector for environmental gas according to the present invention;

[0021] in:

[0022] 1 – filter;

[0023] 21——first solenoid valve;

[0024] 22——second solenoid valve;

[0025] 23——the third solenoid valve;

[0026] 24——the fourth solenoid valve;

[0027] 25——fifth solenoid valve;

[0028] 3——Passivation gas path block;

[0029] 4——Quantitative ring;

[0030] 5——Vacuum pump.

[0031] FIG. 2 is a schematic diagram of a control flow in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] The present invention provides a sample injector (such as Figure 1 As shown), it includes a filter 1, a first solenoid valve 21, a second solenoid valve 22, a third solenoid valve 23, a fourth solenoid valve 24, a fifth solenoid valve 25, a passivation gas circuit block 3, a quantitative ring 4, and an air pump 5 connected by pipelines and a control circuit board.

[0034] One end of the first solenoid valve 21 is connected to the filter 1 , and the other end is connected to the injector inlet of the passivation gas path block 3 .

[0035] One end of the second solenoid valve 22 is connected to the air pump 5 , and the other end is connected to the vent of the passivation gas path block 3 .

[0036] One end of the third solenoid valve 23 is connected to the vent port of the passivation gas circuit block 3 , and the other end is connected to the inlet of the analysis instrument of the passivation gas circuit block 3 .

[0037] One end of the fourth solenoid valve 24 is connected to the carrier gas inlet of the passivation gas path block 3 , and the other end is connected to the analytical instrument inlet of the passivation gas path block 3 .

[0038] One end of the fifth solenoid valve 25 is connected to the carrier gas inlet of the passivation gas path block 3 , and the other end is connected to the injector inlet of the passivation gas path block 3 .

[0039] One end of the quantitative ring 4 is connected to the injector inlet of the passivation gas path block 3 , and the other end is connected to the vent of the passivation gas path block 3 .

[0040] The present invention includes six control processes (as shown in Figure 2), a sampling stage, a sample injection stage, a cavity pressurizing stage during pipeline cleaning, a filter backflushing stage during pipeline cleaning, a cavity re-pressurizing stage during pipeline cleaning, and a quantitative loop flushing stage during pipeline cleaning.

[0041] The following are introduced:

[0042] In the sampling phase (as shown in FIG. 2( a )), the first solenoid valve 21, the second solenoid valve 22, and the fourth solenoid valve 24 are opened, the third solenoid valve 23 and the fifth solenoid valve 25 are closed, and the vacuum pump 5 is turned on. The ambient gas is discharged from the sampler inlet through the filter 1, the quantitative ring 4, and the vacuum pump 5. The carrier gas enters the analyzer inlet from the carrier gas inlet.

[0043] In the sampling stage (as shown in FIG. 2( b) ), during this process, the first solenoid valve 21, the second solenoid valve 22, and the fourth solenoid valve 24 are closed, the third solenoid valve 23 and the fifth solenoid valve 25 are opened, the vacuum pump 5 is closed, and the carrier gas enters from the carrier gas inlet, bringing the gas to be tested in the quantitative ring 4 into the analytical instrument for detection.

[0044] As shown in the cavity pressurization stage during the pipeline cleaning process (Figure 2(c)), during this process, the first solenoid valve 21, the second solenoid valve 22, the third solenoid valve 23, and the fourth solenoid valve 24 are closed, the fifth solenoid valve 25 is opened, the vacuum pump 5 is in a closed state, and the carrier gas enters the quantitative ring 4 from the carrier gas inlet to pressurize the cavity.

[0045] During the filter backflushing stage of the pipeline cleaning process (as shown in Figure 2(d)), the second solenoid valve 22, the third solenoid valve 23, and the fourth solenoid valve 24 are closed, and the first solenoid valve 21 and the fifth solenoid valve 25 are opened, and the pressurized carrier gas is discharged through the injector inlet, thereby backflushing the injector inlet and the filter.

[0046] During the re-pressurization stage of the cavity during the pipeline cleaning process (as shown in Figure 2(e)), the first solenoid valve 21, the second solenoid valve 22, the third solenoid valve 23, and the fourth solenoid valve 24 are closed, the fifth solenoid valve 25 is opened, the vacuum pump 5 is in a closed state, and the carrier gas enters the quantitative ring 4 from the carrier gas inlet to re-pressurize the cavity.

[0047] During the quantitative ring flushing stage of the pipeline cleaning process (as shown in Figure 2(f)), the first solenoid valve 21 and the third solenoid valve 23 of the switch solenoid valve are closed, the fourth solenoid valve 24 is closed, the second solenoid valve 22 and the fifth solenoid valve 25 are opened, and the pressurized carrier gas is discharged through the vent to flush the quantitative ring 4.

[0048] In summary, the present invention overcomes the defect of the existing sampling technology that the six-way valve or the ten-way valve is easily contaminated or even blocked under harsh environmental conditions, and proposes a miniaturized, modular, low-power, and low-cost sampling device, which ensures the accurate quantification, stability, and repeatability of sample collection, and provides a solid technical and material foundation for future analytical instruments, especially the pre-treatment systems of online and portable analytical instruments, and has far-reaching reference significance.

Claims

1. A control method for a sampler for precise quantitative measurement of ambient gas, characterized in that: The sample injector comprises a filter (1), a first solenoid valve (21), a second solenoid valve (22), a third solenoid valve (23), a fourth solenoid valve (24), a fifth solenoid valve (25), a passivation gas path block (3), a quantitative ring (4), and an air pump (5), which are connected to a control circuit board in a pipeline manner; One end of the first solenoid valve (21) is connected to the filter (1), and the other end is connected to the injector inlet of the passivation gas path block (3); One end of the second solenoid valve (22) is connected to the vacuum pump (5), and the other end is connected to the vent of the passivation gas path block (3); One end of the third solenoid valve (23) is connected to the vent port of the passivation gas circuit block (3), and the other end is connected to the inlet of the analysis instrument of the passivation gas circuit block (3); One end of the fourth solenoid valve (24) is connected to the carrier gas inlet of the passivation gas path block (3), and the other end is connected to the analytical instrument inlet of the passivation gas path block (3); One end of the fifth solenoid valve (25) is connected to the carrier gas inlet of the passivation gas path block (3), and the other end is connected to the injector inlet of the passivation gas path block (3); One end of the quantitative loop (4) is connected to the injector inlet of the passivation gas path block (3), and the other end is connected to the vent of the passivation gas path block (3); The control method includes six control processes: a sampling stage, a sample injection stage, a cavity pressurizing stage during pipeline cleaning, a filter backwashing stage during pipeline cleaning, a cavity re-pressurizing stage during pipeline cleaning, and a quantitative loop flushing stage during pipeline cleaning; In the sampling stage: the first solenoid valve (21), the second solenoid valve (22), and the fourth solenoid valve (24) are opened, the third solenoid valve (23) and the fifth solenoid valve (25) are closed, the vacuum pump (5) is turned on, the ambient gas is discharged from the sampler inlet through the filter (1), the quantitative ring (4), and the vacuum pump (5), and the carrier gas enters the analyzer inlet from the carrier gas inlet; In the sampling stage: the first solenoid valve (21), the second solenoid valve (22), and the fourth solenoid valve (24) are closed, the third solenoid valve (23) and the fifth solenoid valve (25) are opened, the vacuum pump (5) is closed, and the carrier gas enters from the carrier gas inlet to bring the gas to be tested in the quantitative loop (4) into the analytical instrument for detection; In the cavity pressurization stage during the pipeline cleaning process: the first solenoid valve (21), the second solenoid valve (22), the third solenoid valve (23), and the fourth solenoid valve (24) are closed, the fifth solenoid valve (25) is opened, the vacuum pump (5) is in a closed state, and the carrier gas enters the quantitative ring (4) from the carrier gas inlet to pressurize the cavity; In the filter backflushing stage during the pipeline cleaning process: the second solenoid valve (22), the third solenoid valve (23), and the fourth solenoid valve (24) are closed, the first solenoid valve (21) and the fifth solenoid valve (25) are opened, and the pressurized carrier gas is discharged through the inlet of the injector, thereby backflushing the filter; In the cavity re-pressurization stage during the pipeline cleaning process: the first solenoid valve (21), the second solenoid valve (22), the third solenoid valve (23), and the fourth solenoid valve (24) are closed, the fifth solenoid valve (25) is opened, the vacuum pump (5) is in a closed state, the carrier gas enters the quantitative ring (4) from the carrier gas inlet, and the cavity is re-pressurized; In the quantitative loop flushing stage of the pipeline cleaning process: the first solenoid valve (21) and the third solenoid valve (23) are closed, the fourth solenoid valve (24) is closed, the second solenoid valve (22) and the fifth solenoid valve (25) are opened, and the pressurized carrier gas is discharged through the vent, thereby flushing the quantitative loop (4).

2. A control method for a sample injector for precise quantitative measurement of environmental gas according to claim 1, characterized in that: The passivation gas path block (3) is made of aluminum alloy or stainless steel and has been passivated.

3. A control method for a sample injector for precise quantitative measurement of environmental gas according to claim 1, characterized in that: The quantitative ring (4) is made of stainless steel and has been passivated.

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